13. November 2003
Portraits of the Moon
The core focus of my interest in photography, and the majority of my subsequent study, has been in the area of portraiture. As a student of all things photographic, I have certainly admired the work of landscape and astronomic photographers, but in choosing a discipline to ultimately master amongst the specialties that exist in modern photography, I chose portraiture.

I casually followed the news surrounding the recent eclipse of November 8, but at first did not expect to photograph the event. After all, this was the realm of astrophotographers armed with telescopes and such. As the day of the eclipse drew closer, I came to realize that my location in the northeast corridor of the United States would give me an optimal view of all phases of the eclipse. The words of a local photographer stuck with me , that every day a photographer should do something photographic, and clearly it would be a shame not to at least make an attempt to capture the eclipse on this especially photographic day. I decided I would try to photograph the eclipse and began to contemplate the technique to do so. I realized that I did have enough horsepower in my gear to remove that as an impediment. I then took a classic photographical viewpoint that photography is photography. From my portraitist’s perspective, I would be taking portraits of the moon.



Equipment
Though I have no bias against film photography, digital photography would be preferable in capturing this event. The tool of choice would be my Nikon D100. With its less than full frame CCD, my focal length would be increased by a factor of 1.5 and, with my longest lens being just 300mm at full zoom, I was going to need all of the focal length I could get. By virtue of using a digital camera, I effectively had a 450mm lens, and after some crude calculations, expected that I should be able to get some printable images. They would need to tolerate enlargement, but I would have to cross that bridge after the pictures were captured.

Setting up
The only potential showstopper would be cloud cover or bad weather . As the day closed in on the time of the eclipse, the sky was entirely clear. I grabbed my tripod and set it up on the front lawn with nothing between me and a head on view of the full moon. The eclipse would start around 6:30 pm EST with full eclipse scheduled for 8:06 pm EST. I set up around 5:30 to allow time for some test shots and set proper exposure. With the instant confirmation that is only possibly with digital photography, I could tell from these test shots that I just might be successful in recording the phases of the eclipse. Excited and encouraged, I endured the increasing chill and continued on.



While this session would take place at night, this would not be typical nighttime photography. The subject of these photos would not be the night sky per se, but the moon itself. The moon, until full eclipse, is a sunlit body. Though it sounds a bit ironic, I thought to use the "sunny 16" rule (f16 at 1/ISO) to establish a baseline for exposure. In choosing ISO, I had some latitude here and this is yet another advantage to doing this digitally. The Nikon D100 offers ISO values ranging from 200 to 1600 (plus two additional settings enabling effectively a 6400 ISO value) so I figured I could set ISO in the 400-800 range and be well within the low noise floor that the D100 provides. Anticipating that I would need to open the aperture wide at near eclipse to get the reddish glow cast by the earth’s shadow that was expected, I wanted to use a fairly fast shutter speed to maximize sharpness. Though it moves relatively slowly, the moon is not perfectly stationary either so fractional shutter speeds would be preferable. I chose an ISO of 640 and set exposure for f16 at 1/400 and took some test shots.

To confirm exposure, I figured I would spot meter the moon at f16 just to see how close the sunny 16 approximation was. The meter returned 1/250. Since the D100’s meter is engineered to favor slight underexposure (the proper way to handle digital exposures) I deferred to its advice and used f16 at 1/250 as my baseline exposure. Because of the discrepancy in my mental calculation versus that of the meter, I decided to bracket my exposures plus and minus 2/3 of a stop. As it turned out, to my eye, the +2/3 EV bracketed exposure, f16 at 1/160, yielded the more pleasing exposure while still retaining lunar detail.

The eclipse


At approximately 6:30 pm, I started recording the phases of the eclipse. Bear in mind that as the eclipse progressed, I expected to have to lengthen exposure to compensate for the loss of light. I took pictures at approximately 10-15 minute intervals, adjusting my tripod’s head each time to follow the lunar arc. This interval seemed adequate to show the progression of the eclipse. For the most part, I kept my exposure bracketed around the original baseline exposure, but as the full eclipse approached I knew that exposure would be insufficient. Since my 300mm lens could only maximally open to f6, I had to compensate the exposure with lengthened shutter speed. Just as in portraiture, in order capture color in dim light, an exposure on the order of one second, I approximated, would be necessary. Whether that would work or whether digital noise would prevent the picture from sustaining enlargement, I could not predict.



For the frame showing the near full eclipse, five minutes before the full eclipse, I used f6 at 1 second and again bracketed for 2/3 EV over and under. Here, the visual difference between 1 second and the +2/3 EV exposure of 1.6 seconds was not as dramatic, but the visual edge goes once again to the greater exposure.

Full eclipse lasted approximately half an hour. Though I intended to capture the moon as it emerged from eclipse, cloud cover set in, obscuring the moon at times, and making the exercise a bit difficult. In light of the cold weather setting in across the northeast and the greater success than I expected with these pictures, I decided to bring in my tripod and call it a night.

While I took nearly 60 exposures throughout the evening, I am presenting just a few samples representative of my shoot. Despite my initial concern that a 300mm lens might not offer enough resolution, I was surprised to record discernable detail on the lunar surface. In particular, the mares are distinguishable and the gradations of light at different phases of the eclipse can be discerned. Even at a 3x enlargement, noise levels are not objectionable.

After studying the pictures on Sunday morning, I realized that these photos would make excellent candidates for some post production editing. While I did not have much time to fully explore the possibilities, a little bit of unsharp masking and color curve augmentation really did wonders for the lunar structure and enhancement of the earth‘s reddish shadow. Philosophically, this opens up the discussion for what is reality versus what is manipulation. This is subject matter for another article entirely. The images presented here are all been given some levels adjustments and sharpening.

In retrospect, I am glad I did not sit by casually and miss this relatively infrequent photo opportunity. The next lunar eclipse visible from the northeast will occur sometime in October 2004 and armed with this experience, the knowledge gained, and perhaps some additional long range gear, I hope to be there with the expectation of capturing greater portraits of the moon.


Arthur Seltzer (aseltzer144@comcast.net)
Essence Imaging, Inc. (www.essence-imaging.com)
Philadelphia, PA USA